fix for validating dm invite from your other installation

[cameronvoell]

Fixes a bug where dm invites were being treated invalid if they came from another installation associated with your inbox_id.

See updated logic with better comments:

libxmtp/xmtp_mls/src/groups/mod.rs

Lines 1705 to 1745 in a85d053

	// 1) Check if the conversation type is DM
	if metadata.conversation_type != ConversationType::Dm {
	return Err(GroupError::Generic(
	"Invalid conversation type for DM group".to_string(),
	));
	}
	// 2) If `dm_members` is not set, return an error immediately
	let dm_members = match &metadata.dm_members {
	Some(dm) => dm,
	None => {
	return Err(GroupError::Generic(
	"DM group must have DmMembers set".to_string(),
	));
	}
	};
	// 3) If the inbox that added this group is our inbox, make sure that
	// one of the `dm_members` is our inbox id
	if added_by_inbox == client.inbox_id() {
	if !(dm_members.member_one_inbox_id == client.inbox_id()
	|| dm_members.member_two_inbox_id == client.inbox_id())
	{
	return Err(GroupError::Generic(
	"DM group must have our inbox as one of the dm members".to_string(),
	));
	}
	return Ok(());
	}
	// 4) Otherwise, make sure one of the `dm_members` is ours, and the other is `added_by_inbox`
	let is_expected_pair = (dm_members.member_one_inbox_id == added_by_inbox
	&& dm_members.member_two_inbox_id == client.inbox_id())
	|| (dm_members.member_one_inbox_id == client.inbox_id()
	&& dm_members.member_two_inbox_id == added_by_inbox);
	if !is_expected_pair {
	return Err(GroupError::Generic(
	"DM members do not match expected inboxes".to_string(),
	));
	}

[cameronvoell]

• fix for validating dm invite from your other installation #1520 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.